Process for the catalytic conversion of hydrocarbons

ABSTRACT

A process for the catalytic conversion of hydrocarbons, said process comprising the following steps:
         a feedstock of hydrocarbons is contacted with a hydrocarbon-converting catalyst to conduct a catalytic cracking reaction in a reactor, then the reaction products are taken from said reactor and fractionated to give light olefins, gasoline, diesel, heavy oil and other saturated hydrocarbons with low molecular weight,   wherein said hydrocarbon-converting catalyst comprises, based on the total weight of the catalyst, 1-60 wt % of a zeolite mixture, 5-99 wt % of a thermotolerant inorganic oxide and 0-70 wt % of clay, wherein said zeolite mixture comprises, based on the total weight of said zeolite mixture, 1-75 wt % of a zeolite beta modified with phosphorus and a transition metal M, 25-99 wt % of a zeolite having a MFI structure and 0-74 wt % of a large pore zeolite,   wherein the anhydrous chemical formula of the zeolite beta modified with phosphorus and the transition metal M is represented in the mass percent of the oxides as (0-0.3)Na 2 O.(0.5-10)Al 2 O 3 .(1.3-10)P 2 O 5 .(0.7-15)M x O y .(64-97)SiO 2 ,   in which the transition metal M is one or more selected from the group consisting of Fe, Co, Ni, Cu, Mn, Zn and Sn; x represents the atom number of the transition metal M, and y represents a number needed for satisfying the oxidation state of the transition metal M.       

     The process of the present invention has a higher ability to convert petroleum hydrocarbon in a higher yield for light olefins, particularly for propylene.

TECHNICAL FIELD

The present invention relates to a process of catalytic conversion ofhydrocarbons, and particularly to a process for the catalytic conversionfor higher selectively producing light olefins from hydrocarbons.

BACKGROUND ART

Ethylene and propylene are typical light olefins which are the mostbasic raw materials in the chemical engineering. In the domestic andforeign, the light olefins are mainly prepared from natural gas or lighthydrocarbons by a steam splitting process in an ethylene combinationunit. The second-largest source of light olefins is from a fluidizedcatalytic cracking (FCC) unit in a refinery. The conventional catalyticcracking process also produces light olefins as by-products with a yieldof only less than 15% of feedstock during the production of gasoline andlight diesels. Specific formulations of a catalytic cracking catalystand/or adjuvant are usually selected in a refinery to improve the yieldof propylene.

U.S. Pat. No. 5,670,037 discloses a process for producing light olefins,wherein the feedstock are petroleum fractions with different boilingranges, residual oil or crude oil. A solid acidic catalyst is used in afluidized bed or moving bed reactor to conduct the catalytic conversionreaction, at a temperature of 480° C. to 680° C. and a pressure of 0.12to 0.40 MPa, with a reaction time of 0.1 to 6 seconds and a weight ratioof catalyst to oil of 4-12, and the spent catalyst is stripped, burntand regenerated, then recycled to the reactor for reuse. Compared to theconventional catalytic cracking and the steam splitting process, theprocess can give more propylene and butylene, wherein the total yield ofbutylene and propylene can reach at about 40%.

U.S. Pat. No. 6,538,169 discloses a process for improving the yield oflight olefins, which comprises, recycling a part of the spent catalystsback to the bottom of the reactor, raising the catalyst to oil ratio,decreasing the temperature at which the catalyst and the oil contact,and adding a ZSM-5 adjuvant to the reaction system.

U.S. Pat. No. 6,791,002B1 discloses a riser system for cracking ofhydrocarbons, wherein the cracking reaction temperature and residencetime of feedstock having different compositions are controlled toimprove the yield of the light olefins. The process didn't mention tooptimize the conversion of components by modifying the active componentsof the catalyst in order to improve the selectivity of the lightolefins.

The catalytic cracking process for obtaining light olefins frompetroleum hydrocarbons have been reported in many patents. Themetal-supported catalysts are used, wherein the carrier are SiO₂, Al₂O₃,or other oxides, and the metal components are mainly selected fromelements of Groups IIB, VB, VIIB, and VIII, which show a hydrogenationor dehydrogenation activity, exhibits a dehydrogenation activity incracking conditions of high temperature and low pressure, and thusaccelerates the production of light olefins (U.S. Pat. No. 3,541,179,U.S. Pat. No. 3,647,682, DD225135 and SU 1214726). When these catalystsare used, owing to the dehydrogenation property of the supported metals,the coke formation due to the polymerization reaction is accordinglyaccelerated during the cracking reaction, and increased coke is formedon the catalyst. Hence, only these light feedstocks with a boiling rangeless than 220° C. can be used.

A composite oxide catalyst is used in some other patents. By ways ofexample of these catalysts, mention will be made of a catalystcomprising ZrO₂, HfO₂ as main components, Al₂O₃, Cr₂O₃, MnO, Fe₂O₃ andoxides of alkaline metal or alkaline earth metal as an adjuvant (U.S.Pat. No. 3,725,495, U.S. Pat. No. 3,839,485); and SiO₂.Al₂O₃ catalystcontaining small amounts of Fe₂O₃, TiO₂, CaO, MgO, Na₂O, and K₂O (SU550173, SU 559946).

With the widespread application of zeolite in the petrochemical andpetroleum processing, there appears the third class of catalysts, i.e.,the catalysts comprising zeolite. In recent years, a shape selectiveadditive is added into a catalyst to enhance the octane number ofcatalytic gasoline. For example, U.S. Pat. No. 3,758,403 discloses acatalyst using ZSM-5 zeolite and a large pore zeolite (with a ratio of1:10 to 3:1) as active components, and in addition to enhancing theoctane number of the gasoline, this catalyst provides a higher yield ofC₃ and C₄ olefins, with a C₃ and C₄ olefins yield of roughly 10% byweight.

When the catalyst contains a mixture of a zeolite with the MFI structure(silicon-rich five-member-ring zeolite) and a zeolite with a pore sizegreater than 7 angstrom is used in the cracking of petroleumhydrocarbons to produce light olefins, the large pore zeolite (Y typezeolite mainly) is used to crack the feedstock to produce gasoline anddiesel, which are further cracked into light olefins by the zeolite withthe MFI structure (U.S. Pat. No. 3,758,403, CN 1043520A, US 500649, andCN 1026242C). To increase the olefin selectivity of catalysts, the MFIzeolite is further modified with, for examples, transition metals (U.S.Pat. No. 5,236,880), phosphorus (CN 1205307A, U.S. Pat. No. 6,566,293),rare earth (CN 1085825A), phosphorus and rare earth (CN 1093101A, U.S.Pat. No. 5,380,690, CN 1114916A, CN 1117518A, CN 1143666A), phosphorusand alkaline earth metals (CN 1221015A, U.S. Pat. No. 6,342,153, CN1222558A, U.S. Pat. No. 6,211,104), and phosphorus and transition metals(CN 1504540A).

The zeolite beta has a 12 member-ring structure with intersected porouschannels, wherein the pore diameter of the 12-member ring is 0.75-0.57nm for the one-dimension porous channel parallel to the (001) crystalface, while the pore diameter of the 12 member-ring is 0.65-0.56 nm forthe two-dimension porous channel parallel to the (100) crystal face. Thezeolite beta is a silicon-rich large pore zeolite having athree-dimension structure that is the only one discovered up to now, andhas both acid catalytic property and structural selectivity due to itsstructural particularity, and further has very high thermostability (thefailure temperature of the crystal lattice is higher than 1200° C.),hydrothermal stability and abrasion-resistant property. Due to theunique structural feature, the zeolite beta has good thermal andhydrothermal stability, acid resistance, anti-coking property andcatalytic activity in a series of catalytic reactions; therefore it hasbeen developed rapidly into a new-type of catalytic materials in recentyears. Many uses of the zeolite beta in the cracking of petroleumhydrocarbons to produce light olefins are reported.

CN 1103105A discloses a cracking catalyst being capable of giving ahigher yield of isobutylene and isoamylene, and said catalyst is acomposite consisting of four active components and a carrier, whereinthe active components consist of a modified HZSM-5 and silicon-richHZSM-5 with different silica/alumina ratios, USY and zeolite beta, thecarrier consists of a natural clay and an inorganic oxide, and thecomponents and contents of the catalyst are as follows: (1) the modifiedHZSM-5 with a silica/alumina ratio of 20 to 100: 5-25% by weight; (2)the silicon-rich HZSM-5 with a silica/alumina ratio of 250 to 450:1-5%by weight; (3) the USY zeolite: 5-20% by weight; (4) the zeolite beta:1-5% by weight; (5) the natural clay: 30-60% by weight; (6) theinorganic oxide: 15-30% by weight. The catalyst has the feature of beingcapable to give a higher yield of isobutylene and isoamylene, while canco-produce a gasoline with a high octane number.

CN 1057408A discloses a cracking catalyst containing a silicon-richzeolite, wherein said catalyst consists of 10-30 wt % of modifiedsilicon-rich zeolite and 70-90 wt % of carrier, said modifiedsilicon-rich zeolite comprises, based on the weight of the zeolite,0.01-3.0 wt % phosphorus, 0.01-1.0 wt % of iron or 0.01-10 wt % ofaluminum (the aluminum in the structure of the zeolite is excluded), andis selected from mordenite, zeolite beta, or ZSM zeolite with asilica/alumina ratio higher than 15, and said carrier is an inorganicoxide or a mixture of an inorganic oxide and kaolin. The catalyst isused to produce light olefins during the catalytic cracking process ofhydrocarbons, and co-produce gasoline and diesel.

CN 1099788A discloses a cracking catalyst being capable of giving ahigher yield of C₃-C₅ olefins, wherein said catalyst consists of 10-50wt % of Y type zeolite with a unit cell size of 2.450 nm or less, 2-40wt % of a zeolite selected from ZSM-5 zeolite or zeolite beta modifiedwith P, RE, Ca, Mg, H, Al, etc. and mixture thereof, 20-80 wt % ofsemi-synthetic carrier consisting of kaolin and alumina binder. Saidcatalyst can enhance the yield of C₃-C₅ olefins wherein yield of iC₄⁼+iC₅ ⁼ is Up to 10-13 wt %, simultaneously keeping the yield ofgasoline at about 35-42 wt %.

CN 1145396A discloses a cracking catalyst being capable of giving ahigher yield of isobutylene and isoamylene, and said catalyst consistsof three active zeolite components and a carrier, based on the weight ofthe catalyst: 6-30 wt % of silicon-rich five-member-ring zeolitecontaining phosphorus and rare earth, 5-25 wt % of USY zeolite, 1-5 wt %of zeolite beta, 30-60 wt % of clay, and 15-30 wt % of inorganic oxide.The catalyst has the feature of being capable to give a higher yield ofisobutylene and isoamylene, while can co-produce a gasoline with a highoctane number.

CN 1354224A discloses a catalytic cracking catalyst for producing agasoline rich in isomeric alkane, propylene and isobutane, wherein saidcatalyst consists of, based on the weight of the catalyst, 0-70 wt % ofclay, 5-90 wt % of inorganic oxide and 1-50 wt % of a zeolite. Thezeolite is a mixture of, based on the weight of the zeolite, (1) 20-75wt % of silicon-rich Y-type zeolite with a silica/alumina ratio of 5-15and RE₂O₃ content of 8-20 wt %, (2) 20-75 wt % of silicon-rich Y-typezeolite with a silica/alumina ratio of 16-50 and RE₂O₃ content of 2-7 wt%, and (3) 1-50 wt % of zeolite beta or mordenite or ZRP zeolite. Thecatalyst can increase the content of the isomeric alkane in the gasolineand simultaneously increase the yield of propylene and isobutane, butthe yield of propylene is just slightly enhanced.

CN 1504541A discloses a catalyst for catalyzing the cracking ofhydrocarbons to produce light olefins and co-produce aromatics,comprising a molecular sieve with a pore size of 0.45-0.7 nm, anamorphous oxide and at least two modifying components selected fromphosphorus, alkaline earth metals, lithium, and rare earth. Saidmolecular sieve is a silica-alumina or silica-phosphor-alumina molecularsieve, wherein said silica-alumina molecular sieve is ZSM-5, ZSM-11,mordenite, or zeolite beta, and said silica-phosphor-alumina molecularsieve is SAPO-5, SAPO-11 or SAPO-34. The active center of the catalystcan be modulated according to the practical needs of products, toprepare the light olefins as main products or co-produce the aromaticsduring the production of olefins.

CN 1566275A discloses a molecular sieve-containing catalyst for crackinghydrocarbons and preparation thereof, said catalyst contains a molecularsieve which is a mixture of a first zeolite and a second zeolite, athermotolerant inorganic oxide and a metal component with or withoutclay, the first zeolite is a Y-type one, the second zeolite is one witha molar ratio of silica to alumina of more than 20, the content of thefirst zeolite is 1-50 wt %, the content of the second zeolite is 1-60 wt%, the content of the thermotolerant inorganic oxide is 2-80 wt %, thecontent of the clay is 0-80 wt %, the content of the metal component is0.1-30 wt %, and said metal components substantially exists as areduction valence state. The catalyst can not only give a high yield ofC₃-C₅ olefins, but also have a higher activity of desulfurization, andfurther have a higher cracking activity. Said second zeolite is one ormore selected from zeolite with MFI structure containing phosphorus,rare earth and/or alkaline earth metal or not, zeolite beta containingphosphorus, rare earth and/or alkaline earth metal or not, mordenitecontaining phosphorus, rare earth and/or alkaline earth metal or not.

U.S. Pat. No. 5,006,497 and U.S. Pat. No. 5,055,176 disclose amulti-component catalyst and the catalytic cracking process thereof.Said catalyst comprises a matrix, a large pore molecular sieve, aparaffin cracking/isomerization molecular sieve and an aromatizationmolecular sieve, wherein said large pore molecular sieve is selectedfrom the group consisting of zeolite Y, DeAlY, USY, UHPY, VPI-5,columnar clay, SAPO-37, zeolite beta and mixtures thereof; said paraffincracking/isomerization molecular sieve is selected from the groupconsisting of hydrogen-type ZSM-5, ZSM-11, ZSM-22, ZSM-35 and ZSM-57;and said aromatization molecular sieve is GaZSM-5.

US 20050070422 discloses a catalyst composition used for increasing theyield of propylene by catalytic cracking, wherein said catalystcomprises a first molecular sieve having an intermediate pore size, asecond molecular sieve having at least one pore size of the channelwhich is less than that of the first molecular sieve, and optionally athird large pore molecular sieve, wherein said first molecular sieve isselected from the group consisting of ZSM-5, ZSM-11, ZSM-12, ZSM-57,ITQ-13 and MCM-22; the second molecular sieve is selected from the groupconsisting of ECR-42, ZSM-22, ZSM-35, ZSM-23, MCM-22, MCM-49, SAPO-11,SAPO-34 and SAPO-41; and the third molecular sieve is selected from thegroup consisting of faujasite, zeolite L, VPI-5, SAPO-37, zeolite X,zeolite beta, ZSM-3, ZSM-4, ZSM-18, ZSM-20, MCM-9, MCM-41, MCM-41S,MCM-48, Y-type zeolite, USY, REY, REUSY and so on. Said catalyst issuitably used for the production of propylene by cracking naphtha andheavy hydrocarbon feedstocks.

With further increasing demand on light olefins, a process for thecatalytic conversion of hydrocarbons is desired to be developed, whereinsaid process exhibits a higher ability to convert petroleum hydrocarbonand higher yield for light olefins, especially propylene.

SUMMARY OF THE INVENTION

The present invention is put forward in view of the aforesaiddevelopment status of the prior art, aiming to provide a catalyticcracking process for higher selectively producing light olefins fromhydrocarbons.

After intensive studies, the inventor finds that, when a hydrocarbonconversion catalyst comprises a specific modified zeolite beta as thecatalyst component, the selectivity of C₂-C₁₂ olefins may be notablyimproved, thus to be advantageous to the production of light olefins(C₂-C₄ olefins) by a further cracking. Thereby, said light olefins canbe produced from petroleum hydrocarbon in a higher yield with thehydrocarbon conversion catalyst which is prepared from said modifiedzeolite beta as an active component, and thereby the present inventionis accomplished.

In order to achieve said purpose, the present invention provides aprocess for the catalytic conversion of hydrocarbons, said processcomprising the following steps:

a feedstock of hydrocarbons is contacted with a hydrocarbon-convertingcatalyst to conduct a catalytic cracking reaction in a reactor in whichthe catalyst is movable, then the reaction product and the spentcatalyst are taken from said reactor for separation by stripping, theseparated spent catalyst is returned into the reactor for recycle afterregenerated by air burning, and the separated reaction product isfractionated to give light olefins, gasoline, diesel, heavy oil andother saturated hydrocarbons with low molecular weight,

wherein said hydrocarbon-converting catalyst comprises, based on thetotal weight of the catalyst, 1-60 wt % of a zeolite mixture, 5-99 wt %of a thermotolerant inorganic oxide and 0-70 wt % of clay, wherein saidzeolite mixture comprises, based on the total weight of said zeolitemixture, 1-75 wt % of a zeolite beta modified with phosphorus and atransition metal M, 25-99 wt % of a zeolite having a MFI structure and0-74 wt % of a large pore zeolite,

wherein the anhydrous chemical formula of the zeolite beta modified withphosphorus and the transition metal M is represented in the mass percentof the oxides as(0-0.3)Na₂O.(0.5-10)Al₂O₃.(1.3-10)P₂O₅.(0.7-15)M_(x)O_(y).(64-97)SiO₂,

in which the transition metal M is one or more selected from the groupconsisting of Fe, Co, Ni, Cu, Mn, Zn and Sn; x represents the atomnumber of the transition metal M, and y represents a number needed forsatisfying the oxidation state of the transition metal M.

Specifically, the present invention relates to:

1. A process for catalytic conversion of hydrocarbons, said processcomprising the following steps:

a feedstock of hydrocarbons is contacted with a hydrocarbon-convertingcatalyst to conduct a catalytic cracking reaction in a reactor in whichthe catalyst is movable, then the reaction product and the spentcatalyst are taken from said reactor for separation by stripping, theseparated spent catalyst is returned into the reactor for recycle afterregenerated by air burning, and the separated reaction product isfractionated to give light olefins, gasoline, diesel, heavy oil andother saturated hydrocarbons with low molecular weight,

wherein said hydrocarbon-converting catalyst comprises, based on thetotal weight of the catalyst, 1-60 wt % of a zeolite mixture, 5-99 wt %of a thermotolerant inorganic oxide and 0-70 wt % of clay, wherein saidzeolite mixture comprises, based on the total weight of said zeolitemixture, 1-75 wt % of a zeolite beta modified with phosphorus and atransition metal M, 25-99 wt % of a zeolite having a MFI structure and0-74 wt % of a large pore zeolite,

wherein the anhydrous chemical formula of the zeolite beta modified withphosphorus and the transition metal M is represented in the mass percentof the oxides as(0-0.3)Na₂O.(0.5-10)Al₂O₃.(1.3-10)P₂O₅.(0.7-15)M_(x)O_(y).(64-97)SiO₂,

in which the transition metal M is one or more selected from the groupconsisting of Fe, Co, Ni, Cu, Mn, Zn and Sn; x represents the atomnumber of the transition metal M, and y represents a number needed forsatisfying the oxidation state of the transition metal M.

2. The process according to Aspect 1, characterized in that thehydrocarbon-converting catalyst comprises, based on the total weight ofthe catalyst, 10-50 wt % of the zeolite mixture, 10-70 wt % of thethermotolerant inorganic oxide and 0-60 wt % of the clay.

3. The process according to Aspect 1, characterized in that theanhydrous chemical formula of the zeolite beta modified with phosphorusand the transition metal M is represented as(0-0.2)Na₂O.(1-9)Al₂O₃.(1.5-7)P₂O₅.(0.9-10)M_(x)O_(y).(75-95)SiO₂.

4. The process according to Aspect 3, characterized in that theanhydrous chemical formula of the zeolite beta modified with phosphorusand the transition metal M is represented as:(0-0.2)Na₂O.(1-9)Al₂O₃.(2-5)P₂O₅.(1-3)M_(x)O_(y).(82-95)SiO₂.

5. The process according to Aspect 1, characterized in that saidtransition metal M is one or more selected from the group consisting ofFe, Co, Ni and Cu.

6. The process according to Aspect 5, characterized in that saidtransition metal M is selected from the group consisting of Fe and/orCu.

7. The process according to Aspect 1, characterized in that the zeolitehaving a MFI structure is one or more selected from the group consistingof ZSM-5 zeolites and ZRP zeolites.

8. The process according to Aspect 7, characterized in that the zeolitehaving a MFI structure is one or more selected from the group consistingof ZRP zeolites containing rare earth, ZRP zeolites containingphosphorus, ZRP zeolites containing phosphorus and rare earth, ZRPzeolites containing phosphorus and alkaline-earth metal and ZRP zeolitescontaining phosphorus and a transition metal.

9. The process according to Aspect 1, characterized in that the largepore zeolite is one or more selected from the group consisting offaujasite, zeolite L, zeolite beta, zeolite Ω, mordenite and ZSM-18zeolite.

10. The process according to Aspect 9, characterized in that the largepore zeolite is one or more selected from the group consisting of Y-typezeolite, Y-type zeolite containing phosphorus and/or rare earth, ultrastable Y-type zeolite, and ultra stable Y-type zeolite containingphosphorus and/or rare earth.

11. The process according to Aspect 1, characterized in that the clay isone or more selected from the group consisting of kaolin, halloysite,montmorillonite, diatomite, endellite, saponite, rectorite, sepiolite,attapulgite, hydrotalcite and bentonite.

12. The process according to Aspect 1, characterized in that the clay isone or more selected from the group consisting of kaolin, halloysite andmontmorillonite.

13. The process according to Aspect 1, characterized in that the reactoris one or more selected from the group consisting of a fluidized bedreactor, a riser, a downward conveying line reactor, and a moving bedreactor, or any combination thereof.

14. The process according to Aspect 13, characterized in that the riseris one or more selected from the group consisting of a riser with equaldiameter, a riser with equal linear velocity and a riser with graduateddiameter.

15. The process according to Aspect 13, characterized in that thefluidized bed reactor is one or more selected from the group consistingof a fixed fluidized bed reactor, a particulate fluidized bed reactor, abubbling bed reactor, a turbulent bed reactor, a fast bed reactor, aconveying bed reactor and a dense phase fluidized bed reactor.

16. The process according to Aspect 1, characterized in that theoperation conditions during the catalytic cracking reaction in thereactor are as follows: the reaction temperature being 480-650° C., theabsolute pressure in the reaction zone being 0.15-0.30 MPa, and theweight hourly space velocity of the hydrocarbon feedstocks being 0.2-40h⁻¹.

17. The process according to Aspect 1, characterized in that thehydrocarbon feedstock is one or more selected from the group consistingof C₄ hydrocarbons, gasoline, diesel, hydrogenation residue, vacuum gasoil, crude oil, and residue oil, or a mixture thereof.

18. The process according to Aspect 1, characterized in that a diluentis added into the reactor during the catalytic cracking reaction toreduce the partial pressure of the hydrocarbon feedstock, wherein thediluent is one or more selected from the group consisting of watervapor, light alkanes, and nitrogen gas, or a mixture thereof.

19. The process according to Aspect 18, characterized in that thediluent is water vapor, and the weight ratio of water vapor to thehydrocarbon feedstock is 0.01-2:1.

According to the hydrocarbon catalytic conversion process of the presentinvention, the hydrocarbon-converting catalyst which has the specificmodified zeolite beta and the zeolite having a MFI structure asessential active components is used, thus exhibiting a higher ability toconvert petroleum hydrocarbons and higher yields for light olefins (ahigher light olefins selectivity), particularly for propylene. As shownin Example 33, under the conditions of a reaction temperature of 600°C., a ratio of catalyst to oil of 10, a weight hourly space velocity of4 h⁻¹, the conversion of feedstock is 94.6%, the yield of C₂-C₄ olefinsis 42.5% wherein the yield of propylene is 21.9%.

THE PREFERRED EMBODIMENTS OF THE INVENTION

In order to produce light olefins from hydrocarbons with a higherselectivity, the present invention provides a process for the catalyticconversion of hydrocarbons, said process comprising the following steps:

a feedstock of hydrocarbons is contacted with a hydrocarbon-convertingcatalyst to conduct a catalytic cracking reaction in a reactor in whichthe catalyst is movable, then the reaction product and the spentcatalyst are taken from said reactor for separation by stripping, theseparated spent catalyst is returned into the reactor for recycle afterregenerated by air burning, and the separated reaction product isfractionated to give light olefins, gasoline, diesel, heavy oil andother saturated hydrocarbons with low molecular weight,

wherein said hydrocarbon-converting catalyst comprises, based on thetotal weight of the catalyst, 1-60 wt % of a zeolite mixture, 5-99 wt %of a thermotolerant inorganic oxide and 0-70 wt % of clay, wherein saidzeolite mixture comprises, based on the total weight of said zeolitemixture, 1-75 wt % of a zeolite beta modified with phosphorus and atransition metal M, 25-99 wt % of a zeolite having a MFI structure and0-74 wt % of a large pore zeolite,

wherein the anhydrous chemical formula of the zeolite beta modified withphosphorus and the transition metal M is represented in the mass percentof the oxides as(0-0.3)Na₂O.(0.5-10)Al₂O₃.(1.3-10)P₂O₅.(0.7-15)M_(x)O_(y)-(64-97)SiO₂,

in which the transition metal M is one or more selected from the groupconsisting of Fe, Co, Ni, Cu, Mn, Zn and Sn; x represents the atomnumber of the transition metal M, and y represents a number needed forsatisfying the oxidation state of the transition metal M.

In the context of the present invention, said term “light olefins”represents C₂-C₄ olefins, unless otherwise specified.

When the process for the catalytic conversion of hydrocarbons providedby the present invention is carried out, the reactor used may be, forexample, selected from the group consisting of a fluidized bed reactor,a riser, a downward conveying line reactor, a moving bed reactor, acomposite reactor consisting of a riser and a fluidized bed reactor, acomposite reactor consisting of a riser and a downward conveying linereactor, a composite reactor consisting of two or more risers, acomposite reactor consisting of two or more fluidized bed reactors, acomposite reactor consisting of two or more downward conveying linereactors, and a composite reactor consisting of two or more moving bedreactors. Further, each of the above said reactors can be divided intotwo or more reaction zones as required.

The riser is one or more selected from the group consisting of a riserwith equal diameter, a riser with equal linear velocity and a riser withgraduated diameter. The fluidized bed reactor is one or more selectedfrom the group consisting of a fixed fluidized bed reactor, aparticulate fluidized bed reactor, a bubbling bed reactor, a turbulentbed reactor, a fast bed reactor, a conveying bed reactor and a densephase fluidized bed reactor.

In the inventive process for the catalytic conversion of hydrocarbons,said hydrocarbon feedstock is one or more selected from the groupconsisting of a C₄ hydrocarbon, gasoline, diesel, hydrogenation residue,vacuum gas oil, crude oil, and residue, or a fraction mixture of thesepetroleum fractions, and also the crude oil and residue can be directlyused.

In one preferred embodiment of the hydrocarbon catalytic conversion ofthe present invention, the hydrocarbon-converting catalyst comprises,based on the total weight of the catalyst, 10-50 wt % of said zeolitemixture, 10-70 wt % of said thermotolerant inorganic oxide and 0-60 wt %of said clay.

The hydrocarbon-converting catalyst of this invention and the method forproducing the same are described in detail as follows.

Said modified zeolite beta as one of the essential components of thehydrocarbon conversion catalyst of the present invention is illuminatedfirstly as follows.

When the anhydrous chemical formula of the zeolite beta modified withphosphorus and the transition metal M is represented in the mass percentof the oxides, the preferred range is:(0-0.2)Na₂O.(1-9)Al₂O₃.(1.5-7)P₂O₅.(0.9-10)M_(x)O_(y).(75-95)SiO₂, morepreferably (0-0.2)Na₂O.(1-9)Al₂O₃.(2-5)P₂O₅.(1-3)M_(x)O_(y).(82-95)SiO₂.

In a preferred embodiment, said transition metal M is one or moreselected from the group consisting of Fe, Co, Ni and Cu, more preferablyFe and/or Cu.

In the hydrocarbon-converting catalyst provided in the presentinvention, said zeolite having a MFI structure represent a silica-richzeolite having a pentasil structure, and is one or more selected fromthe group consisting of ZSM-5 zeolites and ZRP zeolites, particularlyone or more selected from the group consisting of ZRP zeolitescontaining rare earth (see CN 1052290A, CN 1058382A and U.S. Pat. No.5,232,675), ZRP zeolites containing phosphorus (see CN 1194181A, U.S.Pat. No. 5,951,963), ZRP zeolites containing phosphorus and rare earth(see CN 1147420A), ZRP zeolites containing phosphorus and alkaline-earthmetal (see CN 1211469A, CN 1211470A and U.S. Pat. No. 6,080,698) and ZRPzeolites containing phosphorus and a transition metal (see CN 1465527Aand CN 1611299A).

Said large pore zeolite is those having a porous structure having a ringopening of at least 0.7 nm. Said zeolite is, for example, one or moreselected from the group consisting of Y-type zeolite, zeolite L, zeolitebeta, zeolite Ω, mordenite and ZSM-18 zeolite, particularly one or moreselected from the group consisting of Y-type zeolite, Y-type zeolitecontaining phosphorus and/or rare earth, ultra stable Y-type zeolite,and ultra stable Y-type zeolite containing phosphorus and/or rare earth.

In addition, said zeolite having a MFI structure and said large porezeolite may be those commercially available, or may also be prepared byusing various processes known in the art, which are not herein describedin details.

Said zeolite beta modified with phosphorus and the transition metal Mmay be prepared by using various processes. For example, phosphorus andsaid transition metal M may be introduced (1) during the synthesis ofthe zeolite beta; or (2) by the steps of being exchanged with ammonium,being modified with phosphorus, being modified with said transitionmetal M, being calcined and the like after the synthesis of the zeolitebeta.

For example, said zeolite beta modified with phosphorus and thetransition metal M may be prepared according to the following process.That is to say, a sodium-type zeolite beta obtained by a conventionalcrystallization is exchanged in a weight ratio of the zeolite beta:ammonium salt: H₂O=1:(0.1-1):(5-10) at a temperature from roomtemperature to 100° C. for 0.5-2 hour, and filtered. Such an exchangingstep is conducted for 1-4 times, so as to make the content of Na₂O inthe zeolite beta less than 0.2 wt %. Then, by impregnating orion-exchanging, phosphorus and one or more transition metals selectedfrom the group consisting of Fe, Co, Ni, Cu, Mn, Zn and Sn areintroduced into said exchanged zeolite beta to modify the zeolite beta,then dried, and calcined at 400-800° C. for 0.5-8 hours, wherein saidcalcination may be conducted at a steam atmosphere, so as to obtain thezeolite beta modified with phosphorus and the transition metal M.

In the process for preparing the modified zeolite beta of the presentinvention, the modifying process by introducing phosphorus and thetransition metal M into said zeolite can be carried out, for example,through an impregnation or ion-exchange method which is conventional inthis art.

The impregnation can be effected, for instance, through one of the threeways:

a. An ammonium-exchanged zeolite beta filter cake is uniformly mixedwith a predetermined amount of an aqueous solution of a phosphoruscompound at a temperature from room temperature to 95° C., then dried,and calcined at 400-800° C., the resultant solid is uniformly mixed witha predetermined amount of an aqueous solution of a compound containingone or more transition metals M selected from Fe, Co, Ni, Cu, Mn, Zn andSn at a temperature from room temperature to 95° C., then dried;

b. An ammonium-exchanged zeolite beta filter cake is uniformly mixedwith a predetermined amount of an aqueous solution of a phosphoruscompound at a temperature from room temperature to 95° C., then dried,the resultant solid is uniformly mixed with a predetermined amount of anaqueous solution of a compound containing one or more transition metalsM selected from Fe, Co, Ni, Cu, Mn, Zn and Sn at a temperature from roomtemperature to 95° C., then dried, wherein the impregnation sequence ofaforementioned two aqueous solutions can be also reversed; and

c. An ammonium-exchanged zeolite beta filter cake is uniformly mixedwith a predetermined amount of a mixed aqueous solution containing aphosphorus compound and a compound containing one or more transitionmetals M selected from Fe, Co, Ni, Cu, Mn, Zn and Sn at a temperaturefrom room temperature to 95° C., then dried.

Said ion exchange may be given for instance as the following method.

The ammonium-exchanged zeolite beta filter cake is uniformly mixed witha predetermined amount of an aqueous solution of a phosphorus compoundat a temperature from room temperature to 95° C., then dried, andcalcined at 400-800° C., the resultant solid is uniformly mixed with apredetermined amount of an aqueous solution of a compound containing oneor more transition metals M selected from Fe, Co, Ni, Cu, Mn, Zn and Snin a solid/liquid ratio of 1:(5-20), stirred at 80-95° C. for 2-3 hours,then filtered, the exchange step can be repeated many times, the samplethus obtained after exchanging is washed with water many times, thendried.

In the process for preparing the modified zeolite beta of the presentinvention, said ammonium salt is an inorganic one commonly used in theammonium exchange treatment in the art, such as one selected fromammonium chloride, ammonium sulfate and ammonium nitrate, or theirmixture.

In the process for preparing the modified zeolite beta of the presentinvention, said phosphorus compound is one selected from phosphoricacid, diammonium hydrogen phosphate, ammonium dihydrogen phosphate andammonium phosphate, or their mixture.

In the process for preparing the modified zeolite beta of the presentinvention, said compound containing one or more transition metals Mselected from Fe, Co, Ni, Cu, Mn, Zn and Sn is selected from itscorresponding water soluble salts such as their sulfates, nitrates, andchlorides.

In the process for preparing the modified zeolite beta of the presentinvention, said drying may be conducted by the conventional ways, andthe drying temperature may be from room temperature to 350° C.,preferably 100-200° C. In addition, said calcining temperature is theconventional one, generally 400-800° C., preferably 450-700° C.

In the preparation of said modified zeolite beta, the starting zeolitebeta is not particularly defined. The starting zeolite beta may be thosecommonly used in the art or commercially available, or may be preparedaccording to the processes known in the art. In the preferredembodiment, said starting zeolite beta is the sodium-type zeolite beta.If said sodium-type zeolite beta contains an organic template agent, theaforesaid operation should be conducted after removing said organictemplate agent. Moreover, the sodium content in said sodium-type zeolitebeta should satisfy the requirement on the sodium content in theanhydrous chemical formula of the zeolite beta comprising phosphorus andsaid transition metal M. If the sodium content does not satisfy therequirements, the ammonium-exchanging method may be used to removesodium in said starting sodium-type zeolite beta. In this respect, saidammonium-exchanging step is not essential in the preparation of saidmodified zeolite beta.

In the process for preparing said modified zeolite beta of the presentinvention, the devices and condition-regulating methods used therein arenot particularly defined, and they may be conventional devices andcondition-controlling methods in the art.

The following illuminates another essential component, thethermotolerant inorganic oxide, in the hydrocarbon conversion catalystof the present invention.

Said thermotolerant inorganic oxide is not particular defined, but ispreferably selected from one or more of thermotolerant inorganic oxidesused as matrix and binder component of cracking catalyst, e.g., alumina,silica and amorphous silica-alumina. Said thermotolerant inorganic oxideand the preparation processes thereof are known for those skilled in theart. In addition, said thermotolerant inorganic oxide may becommercially available, or may be prepared from the precursors thereofby the processes known in the art.

Additionally, the precursors of said thermotolerant inorganic oxide maybe directly used to replace said thermotolerant inorganic oxide in thepreparation of the hydrocarbon conversion catalyst of the presentinvention. The term “thermotolerant inorganic oxide”, thereby, covers athermotolerant inorganic oxide per se and/or precursors thereof.

The precursors of said thermotolerant inorganic oxide herein representthe substances capable of forming said thermotolerant inorganic oxide inthe preparation of the hydrocarbon conversion catalyst of the presentinvention. Specifically for example, the precursor of said alumina maybe selected from the group consisting of hydrated alumina and/or aluminasol, wherein said hydrated alumina may, for example, be one or moreselected from the group consisting of boehmite, pseudoboehmite, aluminumtrihydrate and amorphous aluminum hydroxide. The precursors of saidsilica may, for example, be one or more selected from the groupconsisting of silica sol, silica gel and water glass. Furthermore, theprecursors of said amorphous silica-alumina may be one or more selectedfrom the group consisting of silica-alumina sol, mixture of silica soland alumina sol, and silica-alumina gel. In addition, the precursors ofsaid thermotolerant inorganic oxide and the preparation processesthereof are also known for those skilled in the art.

The hydrocarbon conversion catalyst of the present invention maycomprise clay as an optional component. Said clay is not particularlydefined, but is preferably one or more selected from the groupconsisting of clays usually as the active components of the crackingcatalyst. For example, the clay is one or more selected from the groupconsisting of kaolin, halloysite, montmorillonite, diatomite, endellite,saponite, rectorite, sepiolite, attapulgite, hydrotalcite and bentonite,preferably one or more selected from the group consisting of kaolin,halloysite and montmorillonite. Said clays and preparation processesthereof are common known for those skilled in the art, or commerciallyavailable.

The following processes are illustrated as the process for thepreparation of the hydrocarbon conversion catalyst of the presentinvention, but the present invention is not limited within the scope ofsaid processes.

All or a part of said thermotolerant inorganic oxide and/or precursorthereof are/is mixed with water, and slurried. To the resulting slurryis optionally added said clay. At this time, the residue of saidthermotolerant inorganic oxide and/or precursor thereof may be furtheradded therein. Said zeolite mixture is added to the slurry, mixed,uniformly slurried, dried and calcined. Before the addition of saidzeolite mixture, before or after the addition of said clay, an acid isadded to the resulting slurry so as to adjust the pH of the slurry to1-5. After the pH falls within the prescribed range, the resultingslurry is aged at 30-90° C. for 0.1-10 hours. After the aging step, theresidue of said thermotolerant inorganic oxide and/or precursor thereofis/are added therein.

In the process for the preparation of the hydrocarbon conversioncatalyst of the present invention, said clay may be added before orafter said aging step. The sequence of adding said clay has no effect onthe properties of the hydrocarbon conversion catalyst of the presentinvention.

In the preparation of the hydrocarbon conversion catalyst of the presentinvention, All or a part of said thermotolerant inorganic oxide and/orprecursor thereof may be added before said aging step. In order toprovide said catalyst with better attrition resistance ability, a partof said thermotolerant inorganic oxide and/or precursor thereof is/areadded preferably before said aging step, and then the residue of saidthermotolerant inorganic oxide and/or precursor thereof is/are addedafter said aging step. In the latter case, the weight ratio of the partadded firstly to the part added later is 1:0.1-10, more preferably1:0.1-5.

In the process for preparing the hydrocarbon conversion catalyst of thepresent invention, an acid is added in order to adjust the pH of theslurry. Said acid is one or more selected from the group consisting ofwater-soluble inorganic acids and organic acids, preferably one or moreselected from the group consisting of hydrochloric acid, nitric acid,phosphoric acid and carboxylic acid having 1-10 carbon atoms, in anamount sufficient to adjust the pH of the slurry to 1-5, preferably1.5-4.

In the process for preparing the hydrocarbon conversion catalyst of thepresent invention, said aging is conducted at 40-80° C. for 0.5-8 hours.

The methods for drying said slurry and conditions are known for thoseskilled in the art. For example, said drying may be selected from thegroup consisting of air drying, baking, forced air drying and spraydrying, preferably spray drying. The drying temperature may be from roomtemperature to 400° C., preferably 100-350° C. In order to be convenientfor the spray drying, the solid content of the slurry before drying ispreferably 10-50 wt %, more preferably 20-50 wt %.

After drying the slurry, the calcination conditions are also known forthose skilled in the art. Generally, the calcination is conducted at400-700° C., preferably 450-650° C. for at least 0.5 hour, preferably0.5-100 hours, more preferably 0.5-10 hours.

After the hydrocarbon-converting catalyst of this invention is prepared,it can be used for the catalytic conversion of hydrocarbons of thisinvention.

In the catalytic conversion of hydrocarbons of this invention, theoperation conditions during the catalytic cracking reaction in thereactor are as follows: a reaction temperature of 480-650° C.,preferably 500-620° C., an absolute pressure of 0.15-0.30 MPa in thereaction zone, preferably 0.2-0.3 MPa. The hydrocarbon feedstock has aweight hourly space velocity of 0.2-40 h⁻¹, preferably 3-30 h⁻¹.

In the catalytic conversion of hydrocarbons of this invention, a diluentmay be added into the reactor during the catalytic cracking reaction toreduce the partial pressure of the hydrocarbon feedstock, wherein thediluent is one or more selected from the group consisting of watervapor, light alkanes, and nitrogen gas, or the like, wherein the watervapor is preferred and the weight ratio of the water vapor to thehydrocarbon feedstock is preferably 0.01-2:1.

In an alternative embodiment of the catalytic conversion of hydrocarbonof this invention, the reaction product and the spent catalyst (the usedcatalyst from the hydrocarbon conversion) are took together from saidreactor for separation, the separated spent catalyst is stripped, andregenerated by air burning, then returned into the reactor for recycle,the separated reaction product is fractionated to give light olefins,gasoline, diesel, heavy oil and other saturated hydrocarbons with lowmolecular weight.

In the catalytic conversion of hydrocarbons of this invention, saidreaction product and the spent catalyst are took together from saidreactor followed by separating via a separator (such as a cycloneseparator). The separated catalyst is again passed through a strippingsection, and the hydrocarbon product adsorbed on the catalyst isstripped by water vapor or other gases. In an alternative embodiment,the stripped catalyst is sent to a regenerator by a fluidizationtechnique to contact with the oxygen-containing gas at a temperature of,for example, 650-720° C. Then the coke deposited on the catalyst isoxidized and burned, thus regenerating the catalyst. Then theregenerated catalyst is returned to the reactor to be recycled. Afterthe separated reaction product (optionally comprising the hydrocarbonproduct obtained in the stripping section) is fractionated by aconventional method, the gas (comprising dry gas and liquefied gas),gasoline, diesel, heavy oil and other saturated hydrocarbons with lowmolecular weight are obtained. Said light olefins comprising ethylene,propylene, and butylene and other components can be separated from saidgas by a known separation technique in this art.

The process for the catalytic conversion of hydrocarbons of thisinvention has the following advantages: by means of using the specificmodified zeolite beta and the zeolite having a MFI structure asessential active components of the hydrocarbon conversion catalyst, itexhibits higher ability to convert the petroleum hydrocarbon, and ahigher yield for light olefins, particularly for propylene.

EXAMPLES

The following examples are used to illustrate further the presentinvention, without limiting the present invention.

Examples 1-10 are used to illuminate the zeolite beta modified withphosphorus and the transition metal M, and the preparation processthereof. Contents of Na₂O, Fe₂O₃, CO₂O₃, NiO, CuO, Mn₂O₃, ZnO, SnO₂,Al₂O₃ and SiO₂ in each sample of the modified zeolites beta are measuredby X-ray fluorescence method (See also Analytical Methods inPetrochemical Industry (RIPP Experiment Techniques), Ed. by Yang Cuidinget. al., Science Press, 1990).

All reagents used as the following are chemical pure reagents; otherwisea special explanation is given.

Example 1

100 g (on dry basis) of the zeolite beta (produced by Qilu CatalystCompany, ratio of SiO₂/Al₂O₃=25) was exchanged and washed with a NH₄Clsolution to a Na₂O content of less than 0.2 wt %, filtering, to obtain afilter cake, 6.8 g H₃PO₄ (concentration of 85%) and 3.2 g Cu(NO₃)₂.3H₂Owere added to and dissolved in 90 g water, then mixed with the filtercake to effect impregnation, dried, calcined at 550° C. for 2 hours,then the modified zeolite beta B1 containing phosphorus and thetransition metal Cu was obtained. Its anhydrous chemical compositionwas:

0.1Na₂O.8.2Al₂O₃.4.0P₂O₅.1.0CuO.86.7SiO₂.

Example 2

100 g (on dry basis) of the zeolite beta was exchanged and washed with aNH₄Cl solution to a Na₂O content of less than 0.2 wt %, filtering, toobtain a filter cake, 12.5 g H₃PO₄ (concentration of 85%) and 6.3 gCuCl₂ were added to and dissolved in 90 g water, then mixed with thefilter cake to effect impregnation, dried, calcined at 550° C. for 2hours, then the modified zeolite beta B2 containing phosphorus and thetransition metal Cu was obtained. Its anhydrous chemical compositionwas:

0.1Na₂O.7.0Al₂O₃.6.9P₂O₅.3.5CuO.82.5SiO₂.

Example 3

100 g (on dry basis) of the zeolite beta was exchanged and washed with aNH₄Cl solution to a Na₂O content of less than 0.2 wt %, filtering, toobtain a filter cake; 4.2 g NH₄H₂PO₄ was dissolved in 60 g water, thenmixed with the filter cake to effect impregnation, dried, calcined at550° C. for 2 hours; aforementioned sample was exchanged with a Cu(NO₃)₂solution (concentration of 5%) in a solid:liquid ratio of 1:5 at 80-90°C. for 2 hours, filtered, the exchange was conducted for several timestill a predetermined amount was reached, then calcined at 550° C. for 2hours, then the modified zeolite beta B3 containing phosphorus and thetransition metal Cu was obtained. Its anhydrous chemical compositionwas:

0.03Na₂O.2.0Al₂O₃.2.5P₂O₅.2.1CuO.93.4SiO₂.

Example 4

100 g (on dry basis) of the zeolite beta was exchanged and washed with aNH₄Cl solution to a Na₂O content of less than 0.2 wt %, filtering, toobtain a filter cake, 7.1 g H₃PO₄ (concentration of 85%) and 8.1 gFe(NO₃)₃.9H₂O were added to and dissolved in 90 g water, then mixed withthe filter cake to effect impregnation, then dried; the obtained samplewas calcined at 55° C. for 2 hours, then the modified zeolite beta B4containing phosphorus and the transition metal Fe was obtained. Itsanhydrous chemical composition was:

0.1Na₂O.6.0Al₂O₃.4.1P₂O₅.1.5Fe₂O₃.88.3SiO₂.

Example 5

100 g (on dry basis) of the zeolite beta was exchanged and washed with aNH₄Cl solution to a Na₂O content of less than 0.2 wt %, filtering, toobtain a filter cake, 10.3 g H₃PO₄ (concentration of 85%) and 39.6 gCo(NO₃)₂.6H₂O were added to and dissolved in 90 g water, then mixed withthe filter cake to effect impregnation, then dried, calcined at 550° C.for 2 hours, then the modified zeolite beta B5 containing phosphorus andthe transition metal Co was obtained. Its anhydrous chemical compositionwas:

0.1Na₂O.6.7Al₂O₃.5.4P₂O₅.9.6CO₂O₃.78.2SiO₂.

Example 6

100 g (on dry basis) of the zeolite beta was exchanged and washed with aNH₄Cl solution to a Na₂O content of less than 0.2 wt %, filtering, toobtain a filter cake, 7.5 g H₃PO₄ (concentration of 85%) and 6.7 gNi(NO₃)₂.6H₂O were added to and dissolved in 90 g water, then mixed withthe filter cake to effect impregnation, then dried; the obtained samplewas calcined at 550° C. for 2 hours, then the modified zeolite beta B6containing phosphorus and the transition metal Ni was obtained. Itsanhydrous chemical composition was:

0.08Na₂O.6.0Al₂O₃.4.3P₂O₅.1.8NiO.87.8SiO₂.

Example 7

100 g (on dry basis) of the zeolite beta was exchanged and washed with aNH₄Cl solution to a Na₂O content of less than 0.2 wt %, filtering, toobtain a filter cake, 6.9 g H₃PO₄ (concentration of 85%) and 16.1 gMn(Q-O₃)₂ were added to and dissolved in 90 g water, then mixed with thefilter cake to effect impregnation, then dried; the obtained sample wascalcined at 550° C. for 2 hours, then the modified zeolite beta B7containing phosphorus and the transition metal Mn was obtained. Itsanhydrous chemical composition was:

0.09Na₂O.1.9Al₂O₃.3.8P₂O₅.6.4Mn₂O₃.87.8SiO₂.

Example 8

100 g (on dry basis) of the zeolite beta, as a crystallized product, wasexchanged and washed with a NH₄Cl solution to a Na₂O content of lessthan 0.2 wt %, filtering, to obtain a filter cake, 2.5 g H₃PO₄(concentration of 85%) and 6.1 g Zn(NO₃)₂.6H₂O were added to anddissolved in 90 g water, then mixed with the filter cake to effectimpregnation, then dried; the obtained sample was calcined at 550° C.for 2 hours, then the modified zeolite beta B8 containing phosphorus andthe transition metal Zn was obtained. Its anhydrous chemical compositionwas:

0.15Na₂O.1.3Al₂O₃.1.5P₂O₅.1.6ZnO.95.8SiO₂.

Example 9

100 g (on dry basis) of the zeolite beta was exchanged and washed with aNH₄Cl solution to a Na₂O content of less than 0.2 wt %, filtering, toobtain a filter cake, 7.1 g H₃PO₄ (concentration of 85%) and 4.2 gSnCl₄.5H₂O were added to and dissolved in 90 g water, then mixed withthe filter cake to effect impregnation, then dried; the obtained samplewas calcined at 550° C. for 2 hours, then the modified zeolite beta B9containing phosphorus and the transition metal Sn was obtained. Itsanhydrous chemical composition was:

0.11Na₂O.6.3Al₂O₃.4.1P₂O₅.1.7SnO₂.87.8SiO₂.

Example 10

100 g (on dry basis) of the zeolite beta was exchanged and washed with aNH₄Cl solution to a Na₂O content of less than 0.2 wt %, filtering, toobtain a filter cake, 7.1 g H₃PO₄ (concentration of 85%), 3.2 gCu(NO₃)₂.3H₂O and 5.3 g Fe(NO₃)₃.9H₂O were added to and dissolved in 90g water, then mixed with the filter cake to effect impregnation, thendried; the obtained sample was calcined at 550° C. for 2 hours, then themodified zeolite beta B10 containing phosphorus and the transitionmetals Cu and Fe was obtained. Its anhydrous chemical composition was:

0.11Na₂O.5.9Al₂O₀.4.1P₂O₅.1.0CuO.1.0Fe₂O₃.87.9SiO₂.

Examples 11-20 are used to illustrate the hydrocarbon conversioncatalyst used in the hydrocarbon catalytic conversion process of thepresent invention, and the preparation process thereof. The startingmaterials used during the preparation of said catalyst are shown asfollows:

Clay:

Halloysite—industrial products by the Suzhou Porcelain Clay Corporation,having a solid content of 71.6%;

Kaolin—industrial products by the Suzhou Kaolin Corporation, having asolid content of 76%;

Montmorillonite—industrial products by the Zhejiang Fenghong Clay Co.,Ltd, having a solid content of 95%.

Thermotolerant inorganic oxide or the precursor thereof:

Pseudoboehmite—industrial products by the Shandong Aluminum Factory,having a solid content of 62.0%;

Alumina sol—produced by the Qilu Catalyst Factory, having aAl₂O₃-content of 21.5%; and

Silica sol—produced by the Beijing Chemical Factory, having asilica—content of 16.0%.

All large pore zeolite are produced by the Qilu Catalyst Factory, andthe industrial trademarks are as follows:

DASY 2.0 has the physicochemical parameters of unit cell size of 2.446nm, Na₂O content of 1.1%, rare earth oxide RE₂O₃ content of 2.0%,wherein lanthanum oxide is in an amount of 1.06%; cerium oxide is in anamount of 0.26%; and other rare earth oxides are in an amount of 0.68%;

USY has the physicochemical parameters of unit cell size of 2.445 nm,and Na₂O content of 0.36%.

DASY 0.0 has the physicochemical parameters of unit cell size of 2.443nm, and Na₂O content of 0.85%.

DASY 6.0 has the physicochemical parameters of unit cell size of 2.451nm, Na₂O content of 1.6%, rare earth oxide RE₂O₃ content of 6.2%,wherein lanthanum oxide is in an amount of 3.29%; cerium oxide is in anamount of 0.81%; and other rare earth oxides are in an amount of 2.10%.

REHY has the physicochemical parameters of unit cell size of 2.465 nm,Na₂O content of 3.2%, rare earth oxide RE₂O₃ content of 7.0%, whereinlanthanum oxide is in an amount of 3.71%; cerium oxide is in an amountof 0.91%; and other rare earth oxides are in an amount of 2.38%.

All of the zeolite having a MFI structure are produced by the QiluCatalyst Factory, and the industrial trademarks are as follows:

ZSP-2, wherein SiO₂/Al₂O₃=70, comprising 0.03% of Na₂O, 4.9% of P₂O₅,and 2.1% of Fe₂O₃;

ZRP-1, wherein SiO₂/Al₂O₃=30, comprising 0.17% of Na₂O, 1.4% of rareearth oxide RE₂O₃, wherein lanthanum oxide is in an amount of 0.84%;cerium oxide is in an amount of 0.18%; and other rare earth oxides arein an amount of 0.38%;

ZSP-1, wherein SiO₂/Al₂O₃=30, comprising 0.1% of Na₂O, 2.0% of P₂O₅, and0.9% of Fe₂O₃; and

ZRP-5, wherein SiO₂/Al₂O₃=50, comprising 0.05% of Na₂O, and 4.0% ofP₂O₅.

Example 11

6.3 kg of halloysite was added to 25.0 kg of decationized water, andslurried. 4.0 kg of pseudoboehmite was added therein, adjusting the pHthereof to 2 with hydrochloric acid, uniformly stirred and aged bystanding at 70° C. for 1 hour. Then, 1.4 kg of alumina sol (the weightratio of the thermotolerant inorganic oxide (or precursor thereof) addedbefore and after aging is 1:0.12) was added, after uniformly stirred,7.7 kg of slurry obtained by slurrying a mixture of 0.6 kg (on drybasis) of modified zeolite beta B1, 0.6 kg (on dry basis) of ultrastable zeolite-Y DASY 2.0 and 1.5 kg (on dry basis) of zeolite ZSP-2having a MFI structure with water was added, and uniformly stirred toyield a slurry with a solid content of 22.5 wt %. The resulting slurrywas spray-dried and shaped into particles with diameter of 20-150 μm at250° C. Then the obtained particles were calcined at 550° C. for 2hours, to yield catalyst C1. The composition of C1 is shown in Table 1.

Example 12

Catalyst C2 was prepared according to the process in Example 11, exceptfor replacing the zeolite beta B1 with the modified zeolite beta B2 inthe same amount. The composition of C2 is shown in Table 1.

Example 13

Catalyst C3 was prepared according to the process in Example 11, exceptfor replacing the zeolite beta B1 with the modified zeolite beta B4 inthe same amount. The composition of C3 is shown in Table 1.

Example 14

Catalyst C4 was prepared according to the process in Example 11, exceptfor replacing the zeolite beta B1 with the modified zeolite beta B10 inthe same amount. The composition of C4 is shown in Table 1.

Comparative Example 1

This comparative example describes the reference catalysts containingzeolite beta which is not modified with phosphorus and the transitionmetal, and the preparation process thereof.

Reference catalyst CB1 was prepared according to the process in Example11, except for replacing the zeolite beta B1 with the zeolite beta (sameas Example 1) which is not modified with phosphorus and the transitionmetal. The composition of CB1 is shown in Table 1.

Comparative Example 2

This comparative example discloses the reference catalysts containing nozeolite beta, and the preparation process thereof.

Reference catalyst CB2 was prepared according to the process in Example11 except for no zeolite beta was added, and the ultra stable zeolite-YDASY 2.0 was in an amount of 1.2 kg (on dry basis). The composition ofCB2 is shown in Table 1.

TABLE 1 Example No. Comp. Comp. Ex. 11 Ex. 12 Ex. 13 Ex. 14 Ex. 1 Ex. 2Types of the B1 B2 B4 B10 unmodified — modified zeolite beta ModifyingP₂O₅, 4.0 P₂O₅, 6.9 P₂O₅, 4.1 P₂O₅, 4.1 — — elements and CuO, 1.0 CuO,3.5 Fe₂O₃, 1.5 CuO, 1.0 contents thereof, Fe₂O₃, wt % 1.0 Catalyst C1 C2C3 C4 CB1 CB2 Composition of the catalyst, wt % Halloysite 45 45 45 4545 45 Thermotolerant 28 28 28 28 28 28 inorganic oxide DASY 2.0 6 6 6 66 12 ZSP-2 15 15 15 15 15 15 Modified zeolite 6 6 6 6 6 — beta

Example 15

4.0 kg of pseudoboehmite was added to 12.5 kg of decationized water,adjusting the pH thereof to 2 with nitric acid, uniformly stirred andaged by standing at 50° C. for 5 hours to yield an aged product.

2.3 kg of alumina sol (the weight ratio of the thermotolerant inorganicoxide (or precursor thereof) added before and after aging is 1:0.2) wasadded to 2.5 kg of decationized water. 4.0 kg of kaolin was addedtherein, slurried and uniformly stirred. Then, the above aged productand 11.4 kg of slurry obtained by slurrying a mixture of 0.5 kg (on drybasis) of modified zeolite beta B3, 2.5 kg (on dry basis) of ultrastable zeolite-Y USY and 1.0 kg (on dry basis) of the zeolite ZRP-1having a MFI structure with the decationized water were added, anduniformly stirred to yield a slurry with a solid content of 27.2 wt %.The resulting slurry was spray-dried and shaped into particles withdiameter of 20-150 μm at 220° C. Then the obtained particles werecalcined at 520° C. for 4 hours, to yield catalyst C5. The compositionof C5 is shown in Table 2.

Example 16

3.9 kg of kaolin and 1.1 kg of montmorillonite was added to 18.0 kg ofdecationized water, and slurried. 4.0 kg of pseudoboehmite (thethermotolerant inorganic oxide precursors were added before aging) wasadded therein, adjusting the pH thereof to 3 with hydrochloric acid,uniformly stirred and aged by standing at 60° C. for 2 hours. Then, 10.0kg of slurry obtained by slurrying a mixture of 2.0 kg (on dry basis) ofmodified zeolite beta B5 containing phosphorus and the transition metalCo, 0.5 kg (on dry basis) of zeolite-Y REHY and 1.0 kg (on dry basis) ofthe zeolite ZRP-1 having a MFI structure with water was added, anduniformly stirred to yield a slurry with a solid content of 27.0 wt %.The resulting slurry was spray-dried and shaped into particles withdiameter of 20-150 μm at 280° C. Then the obtained particles werecalcined at 580° C. for 2.5 hours, to yield catalyst C6. The compositionof C6 is shown in Table 2.

Example 17

4.2 kg of halloysite was added to 17.8 kg of decationized water, andslurried. 4.0 kg of pseudoboehmite was added therein, adjusting the pHthereof to 3.5 with hydrochloric acid, uniformly stirred and aged bystanding at 75° C. for 0.5 hour. 2.3 kg of alumina sol (the weight ratioof the thermotolerant inorganic oxide (or precursor thereof) addedbefore and after aging is 1:0.2) was added therein, uniformly stirred.Then 11.4 kg of slurry obtained by slurrying a mixture of 1.0 kg (on drybasis) of modified zeolite beta B6 containing phosphorus and thetransition metal Ni, 1.0 kg (on dry basis) of ultra stable zeolite-YDASY 0.0 and 2.0 kg (on dry basis) of the zeolite ZSP-1 having a MFIstructure with water was added, and uniformly stirred to yield a slurrywith a solid content of 25.2 wt %. The resulting slurry was spray-driedand shaped into particles with diameter of 20-150 μm at 250° C. Then theobtained particles were calcined at 600° C. for 1 hour, to yieldcatalyst C7. The composition of C7 is shown in Table 2.

Example 18

4.9 kg of halloysite was added to 20.0 kg of decationized water, andslurried. 4.0 kg of pseudoboehmite was added therein, adjusting the pHthereof to 3.5 with hydrochloric acid, uniformly stirred and aged bystanding at 75° C. for 0.5 hour. 2.3 kg of alumina sol (the weight ratioof the thermotolerant inorganic oxide (or precursor thereof) addedbefore and after aging is 1:0.2) was added therein, uniformly stirred.Then, 10.0 kg of slurry obtained by slurrying a mixture of 0.2 kg (ondry basis) of modified zeolite beta B7 containing phosphorus and thetransition metal Mn, 0.8 kg (on dry basis) of ultra stable zeolite-YDASY 2.0 and 2.5 kg (on dry basis) of the zeolite ZSP-1 having a MFIstructure with water was added, and uniformly stirred to yield a slurrywith a solid content of 24.3 wt %. The resulting slurry was spray-driedand shaped into particles with diameter of 20-150 μm at 250° C. Then theobtained particles were calcined at 600° C. for 1 hour, to yieldcatalyst C8. The composition of C8 is shown in Table 2.

Example 19

3.5 kg of halloysite was added to 15.6 kg of decationized water, andslurried. 4.0 kg of pseudoboehmite was added therein, adjusting the pHthereof to 4 with hydrochloric acid, uniformly stirred and aged bystanding at 60° C. for 1 hour. 4.7 kg of alumina sol (the weight ratioof the thermotolerant inorganic oxide (or precursor thereof) addedbefore and after aging is 1:0.4) was added therein, uniformly stirred.Then, 11.4 kg of slurry obtained by slurrying a mixture of 0.5 kg (ondry basis) of modified zeolite beta B8, 0.5 kg (on dry basis) of ultrastable zeolite-Y DASY 6.0 and 3.0 kg (on dry basis) of the zeolite ZRP-5having a MFI structure with water was added, and uniformly stirred toyield a slurry with a solid content of 25.5 wt %. The resulting slurrywas spray-dried and shaped into particles with diameter of 20-150 μm at220° C. Then the obtained particles were calcined at 550° C. for 2hours, to yield catalyst C9. The composition of C9 is shown in Table 2.

Example 20

3.2 kg of halloysite was added to 12.0 kg of decationized water to beslurried. The pH of the slurry was adjusted to 3 with hydrochloric acid,uniformly stirred and aged by standing at 55° C. for 6 hours. 21.9 kg ofsilica sol and 2.3 kg of alumina sol (the weight ratio of thethermotolerant inorganic oxide (or precursor thereof) added before andafter aging is 1:2) were added therein, and uniformly stirred. Then,11.4 kg of slurry obtained by slurrying a mixture of 1.0 kg of (on drybasis) of modified zeolite beta B9, 3.0 kg of (on dry basis) of thezeolite ZRP-5 having a MFI structure with water was added, and uniformlystirred to yield a slurry with a solid content of 19.7 wt %. Theresulting slurry was spray-dried and shaped into particles with diameterof 20-150 μm at 250° C. Then the obtained particles were calcined at550° C. for 2 hours, to yield catalyst C10. The composition of C10 isshown in Table 2.

TABLE 2 Example No. Ex. 15 Ex. 16 Ex. 17 Ex. 18 Ex. 19 Ex. 20 CatalystC5 C6 C7 C8 C9 C10 Clay: Type kaolin kaolin + halloysite halloysitehalloysite — montmorillonite Content, wt % 30 40 30 35 25 —Thermotolerant inorganic oxide: Type alumina alumina alumina aluminaalumina alumina + silica Content, wt % 30 25 30 30 35 60 Large porezeolite: Type USY REHY DASY DASY DASY — 0.0 2.0 6.0 Content, wt % 25  510  8  5 — Zeolite having a MFI structure: Type ZRP-1 ZRP-1 ZSP-1 ZSP-1ZRP-5 ZRP-5 Content, wt % 10 10 20 25 30 30 Zeolite beta: Type B3 B5 B6B7 B8 B9 Content, wt %  5 20 10  2  5 10 Types of P₂O₅, P₂O₅, 5.4 P₂O₅,4.3 P₂O₅, 3.8 P₂O₅, P₂O₅, 4.1 modifying 2.5 Co₂O₃, 9.6 NiO, 1.8 Mn₂O₃,1.5 SnO₂, 1.7 elements and CuO, 6.4 ZnO, 1.6 contents thereof, 2.1 wt %

Examples 21-24

Examples 21-24 are used to illuminate the catalytic conversion effectsby hydrocarbon-converting catalyst provided in the present invention.

Catalysts of C1-C4 were aged with 100% steam at 800° C. for 14 hours. Asmall sized fixed fluidized bed reactor was used, and 180 g of thecatalyst was fed into the reactor. The aged catalysts were respectivelyevaluated by introducing the mixture of vacuum gas oil and steam(wherein the amount of steam was 25% by weight of the vacuum gas oil)under the conditions of a reaction temperature of 560° C., a catalyst tooil ratio of 10 and a weight hourly space velocity of 4 h⁻¹. Theproperties of the vacuum gas oil are shown in Table 3, the evaluationresults are shown in Table 4.

Comparative Examples 3-4

Comparative Examples 3-4 are used to illustrate the catalytic conversioneffects on hydrocarbons of the reference catalysts.

The effects of the reference catalysts CB1 and CB2 are evaluated usingthe same feed oil according to the process in Example 21, and theresults are shown in Table 4.

TABLE 3 Atmospheric Feed oil Vacuum gas oil residue Density (20° C.),g/cm³ 0.8764 0.8906 Viscosity (80° C.), mm²/s 12.06 24.84 Asphaltene, wt% — 0.8 Conradson carbon residue, wt % 0.93 4.3 Distillation range, ° C.IBP 246 282 10 vol % 430 370 30 vol % 482 482 50 vol % 519 553 70 vol %573(75.2 vol %) — 90 vol % — — FBP — —

TABLE 4 Ex. No. Comp. Comp. Ex. 21 Ex. 22 Ex. 23 Ex. 24 Ex. 3 Ex. 4Catalyst C1 C2 C3 C4 CB1 CB2 Conversion 90.2 90.0 90.4 90.7 88.7 88.1Product distribution, wt % Dry gas 10.0 10.5 10.1 10.1 9.1 8.6 LPG 45.444.6 45.8 46.1 44.0 43.6 Gasoline 22.4 22.3 22.2 21.7 23.9 24.7 Diesel5.5 5.6 5.4 5.3 5.9 6.2 Heavy oil 4.3 4.4 4.2 4.0 5.4 5.7 Coke 12.4 12.612.3 12.8 11.7 11.2 wherein Ethylene 5.2 5.3 5.5 5.4 5.1 4.7 Propylene18.5 18.3 18.8 19.1 18.0 17.9 Butylene 12.8 12.7 12.9 12.8 12.2 11.9

The results in Table 4 showed that, as compared with the process for thecatalytic conversion of hydrocarbons using reference catalyst CB1 agedat the same conditions and having the same zeolite content in which thezeolite beta was not modified, the hydrocarbon catalytic conversion ofthe present invention increased the capability for cracking heavy oilsby 1.3-2%; the LPG yield by 0.6-2.1%; the light olefins (C₂ ⁼+C₃ ⁼+C₄ ⁼)yield by 1-2%; as compared with the reference catalyst CB2 containing nozeolite beta, the hydrocarbon catalytic conversion of the presentinvention increased the capability for cracking heavy oils by 1.9-2.6%;the LPG yield by 1.0-2.5%; the light olefins (C₂ ⁼+C₃ ⁼+C₄ ⁼) yield by1.8-2.8%.

Examples 25-30

Examples 25-30 are used to illustrate the reaction results underdifferent reaction conditions.

Catalysts of C5-C10 were aged with 100% steam at 800° C. for 17 hours. Asmall sized fixed fluidized bed reactor was used, and 180 g of thecatalyst was fed into the reactor. The aged catalysts were respectivelyevaluated by introducing the atmospheric residue. The properties of theatmospheric residue are shown in Table 3, and the reaction conditionsand product distribution is shown in Table 5.

TABLE 5 Example No. Ex. 25 Ex. 26 Ex. 27 Ex. 28 Ex. 29 Ex. 30 CatalystC5 C6 C7 C8 C9 C10 Reaction temperature, ° C. 520 520 580 580 620 620Catalyst/oil weight ratio 10 10 10 10 10 10 Weight hourly space 10 10 1515 20 20 velocity, h⁻¹ Weight percent of steam in 12.5 12.5 25 25 37.537.5 the atmospheric residue, wt % Conversion 79.5 78.9 85.6 83.4 86.586.6 Product distribution, % Dry gas 5.6 5.5 10.3 9.8 12.7 12.6 LPG 21.921.8 39.8 40.7 43.2 42.5 Gasoline 43.4 43.1 23.3 22.4 18.3 18.1 Diesel14.0 14.1 9.9 10.3 8.6 8.6 Heavy oil 6.5 7.0 4.5 6.3 4.9 4.8 Coke 8.68.5 12.2 10.5 12.3 13.4 wherein Ethylene 1.5 1.4 5.2 5.1 6.8 6.8Propylene 6.5 6.7 13.5 16.7 21.6 21.1 Butylene 6.2 7.0 12.8 12.5 14.314.6

Examples 31-33

Examples 31-33 are used to illustrate the cracking results ofhydrocarbons under different reaction temperatures.

Catalyst C4 was aged with 100% steam at 800° C. for 14 hours. A smallsized fixed fluidized bed reactor was used, and 180 g of the catalystwas fed into the reactor. The mixture of vacuum gas oil and steam(wherein the amount of steam was 25% by weight of the vacuum gas oil) asshown in Table 3 is introduced under the conditions of differentreaction temperatures, a catalyst to oil ratio of 10 and a weight hourlyspace velocity of 4 h⁻¹, and the results are shown in Table 6.

TABLE 6 Example No. Ex. 31 Ex. 32 Ex. 33 Catalyst C4 C4 C4 Reactiontemperature, ° C. 520 560 600 Conversion 79.3 90.7 94.6 Productdistribution, % Dry gas 5.2 10.1 14.3 LPG 21.9 46.1 49.5 Gasoline 43.621.7 16.5 Diesel 13.6 5.3 3.4 Heavy oil 7.1 4.0 2.0 Coke 8.6 12.8 14.3wherein Ethylene 1.5 5.4 7.1 Propylene 7.5 19.1 21.9 Butylene 6.2 12.813.5

Examples 34-36

Examples 34-36 are used to illustrate the cracking results ofhydrocarbons under different weight hourly space velocities.

Catalyst C4 was aged with 100% steam at 800° C. for 14 hours. A smallsized fixed fluidized bed reactor was used, and 180 g of the catalystwas fed into the reactor. The mixture of vacuum gas oil and steam(wherein the amount of steam was 25% by weight of the vacuum gas oil) asshown in Table 3 is introduced under the conditions of a reactiontemperature of 560° C., a catalyst to oil ratio of 10 and differentweight hourly space velocities, and the results are shown in Table 7.

TABLE 7 Example No. Ex. 34 Ex. 35 Ex. 36 Catalyst C4 C4 C4 Weight hourlyspace velocity, hour⁻¹ 4 8 12 Conversion 90.7 89.9 88.9 Productdistribution, % Dry gas 10.1 9.5 8.9 LPG 46.1 43.5 41.4 Gasoline 21.724.8 27.1 Diesel 5.3 5.6 6.2 Heavy oil 4.0 4.5 4.9 Coke 12.8 12.1 11.5wherein Ethylene 5.4 5.1 4.7 Propylene 19.1 18.6 18.1 Butylene 12.8 12.411.9

Examples 37-39

Examples 37-39 are used to illustrate the cracking results ofhydrocarbons under different catalyst/oil weight ratios.

Catalyst C4 was aged with 100% steam at 800° C. for 14 hours. A smallsized fixed fluidized bed reactor was used, and 180 g of the catalystwas fed into the reactor. The mixture of vacuum gas oil and steam(wherein the amount of steam was 25% by weight of the vacuum gas oil) asshown in Table 3 is introduced under the conditions of a reactiontemperature of 560° C., a weight hourly space velocity of 4 h⁻¹, anddifferent weight hourly space velocities, and the results are shown inTable 8.

TABLE 8 Example No. Ex. 37 Ex. 38 Ex. 39 Catalyst C4 C4 C4 Catalyst/oilweight ratio 10 15 20 Conversion 90.7 91.4 92.1 Product distribution, %Dry gas 10.1 10.6 11.1 LPG 46.1 46.7 47.2 Gasoline 21.7 20.8 20.1 Diesel5.3 5 4.6 Heavy oil 4 3.6 3.3 Coke 12.8 13.3 13.7 wherein Ethylene 5.45.5 5.7 Propylene 19.1 19.3 20.1 Butylene 12.8 13.2 13.4

1. A process for the catalytic conversion of hydrocarbons, said processcomprising the following steps: a feedstock of hydrocarbons is contactedwith a hydrocarbon-converting catalyst to conduct a catalytic crackingreaction in a reactor in which the catalyst is movable, then thereaction product and the spent catalyst are taken from said reactor forseparation by stripping, the separated spent catalyst is returned intothe reactor for recycle after regenerated by air burning, and theseparated reaction product is fractionated to give light olefins,gasoline, diesel, heavy oil and other saturated hydrocarbons with lowmolecular weight, characterized in that said hydrocarbon-convertingcatalyst comprises, based on the total weight of the catalyst, 1-60 wt %of a zeolite mixture, 5-99 wt % of a thermotolerant inorganic oxide and0-70 wt % of clay, wherein said zeolite mixture comprises, based on thetotal weight of said zeolite mixture, 1-75 wt % of a zeolite betamodified with phosphorus and a transition metal M, 25-99 wt % of azeolite having a MFI structure and 0-74 wt % of a large pore zeolite,wherein the anhydrous chemical formula of the zeolite beta modified withphosphorus and the transition metal M is represented in the mass percentof the oxides as(0-0.3)Na₂O.(0.5-10)Al₂O₃.(1.3-10)P₂O₅.(0.7-15)M_(x)O_(y).(64-97)SiO₂,in which the transition metal M is one or more selected from the groupconsisting of Fe, Co, Ni, Cu, Mn, Zn and Sn; x represents the atomnumber of the transition metal M, and y represents a number needed forsatisfying the oxidation state of the transition metal M.
 2. The processaccording to claim 1, characterized in that the hydrocarbon-convertingcatalyst comprises, based on the total weight of the catalyst, 10-50 wt% of the zeolite mixture, 10-70 wt % of the thermotolerant inorganicoxide and 0-60 wt % of the clay.
 3. The process according to claim 1,characterized in that the anhydrous chemical formula of the zeolite betamodified with phosphorus and the transition metal M is represented as(0-0.2)Na₂O.(1-9)Al₂O₃.(1.5-7)P₂O₅.(0.9-10)M_(x)O_(y).(75-95)SiO₂. 4.The process according to claim 3, characterized in that the anhydrouschemical formula of the zeolite beta modified with phosphorus and thetransition metal M is represented as:(0-0.2)Na₂O.(1-9)Al₂O₃.(2-5)P₂O₅.(1-3)M_(x)O_(y).(82-95)SiO₂.
 5. Theprocess according to claim 1, characterized in that said transitionmetal M is one or more selected from the group consisting of Fe, Co, Niand Cu.
 6. The process according to claim 5, characterized in that saidtransition metal M is selected from the group consisting of Fe and/orCu.
 7. The process according to claim 1, characterized in that thezeolite having a MFI structure is one or more selected from the groupconsisting of ZSM-5 zeolites and ZRP zeolites.
 8. The process accordingto claim 7, characterized in that the zeolite having a MFI structure isone or more selected from the group consisting of ZRP zeolitescontaining rare earth, ZRP zeolites containing phosphorus, ZRP zeolitescontaining phosphorus and rare earth, ZRP zeolites containing phosphorusand alkaline-earth metal and ZRP zeolites containing phosphorus and atransition metal.
 9. The process according to claim 1, characterized inthat the large pore zeolite is one or more selected from the groupconsisting of faujasite, zeolite L, zeolite beta, zeolite Ω, mordeniteand ZSM-18 zeolite.
 10. The process according to claim 9, characterizedin that the large pore zeolite is one or more selected from the groupconsisting of Y-type zeolite, Y-type zeolite containing phosphorusand/or rare earth, ultra stable Y-type zeolite, and ultra stable Y-typezeolite containing phosphorus and/or rare earth.
 11. The processaccording to claim 1, characterized in that the clay is one or moreselected from the group consisting of kaolin, halloysite,montmorillonite, diatomite, endellite, saponite, rectorite, sepiolite,attapulgite, hydrotalcite and bentonite.
 12. The process according toclaim 1, characterized in that the clay is one or more selected from thegroup consisting of kaolin, halloysite and montmorillonite.
 13. Theprocess according to claim 1, characterized in that the reactor is oneor more selected from the group consisting of a fluidized bed reactor, ariser, a downward conveying line reactor, and a moving bed reactor, orany combination thereof.
 14. The process according to claim 13,characterized in that the riser is one or more selected from the groupconsisting of a riser with equal diameter, a riser with equal linearvelocity and a riser with graduated diameter.
 15. The process accordingto claim 13, characterized in that the fluidized bed reactor is one ormore selected from the group consisting of a fixed fluidized bedreactor, a particulate fluidized bed reactor, a bubbling bed reactor, aturbulent bed reactor, a fast bed reactor, a conveying bed reactor and adense phase fluidized bed reactor.
 16. The process according to claim 1,characterized in that the operation conditions during the catalyticcracking reaction in the reactor are as follows: the reactiontemperature being 480-650° C., the absolute pressure in the reactionzone being 0.15-0.30 MPa, and the weight hourly space velocity of thehydrocarbon feedstocks being 0.2-40 h⁻¹.
 17. The process according toclaim 1, characterized in that the hydrocarbon feedstock is one or moreselected from the group consisting of C₄ hydrocarbons, gasoline, diesel,hydrogenation residue, vacuum gas oil, crude oil, and residue oil, or amixture thereof.
 18. The process according to claim 1, characterized inthat a diluent is added into the reactor during the catalytic crackingreaction to reduce the partial pressure of the hydrocarbon feedstock,wherein the diluent is one or more selected from the group consisting ofwater vapor, light alkanes, and nitrogen gas, or a mixture thereof. 19.The process according to claim 18, characterized in that the diluent iswater vapor, and the weight ratio of water vapor to the hydrocarbonfeedstock is 0.01-2:1.